Windows are a key part of any home – they let in light and air, add a touch of style, and connect you to the outside world. But sometimes, streaks can form on windows, leaving them looking dirty and smeared. Taking care of these streaks is important, but not always particularly easy. In this blog, we’re going to explore what’s causing your window streaking issues and how you can fix it moving forward!

Main Causes of Window Streaks

There are a few key items that can lead to seemingly-endless window streaking, and doing what you can to mitigate them will help prevent ongoing issues. Below are the most common culprits of what causes streaks on windows.


Sunny Days

When the sun is shining brightly, it can cause windows to heat up significantly – and as they cool down, any moisture that’s present will condense and form streaks. This is particularly common in older homes with single-pane windows but can happen with double- or triple-paned windows as well.

To help prevent this, you can try to keep your windows shaded during the hottest times of the day using curtains, blinds, or reflective film. This will help reduce the amount of heat that’s builds up in your home and hopefully prevent those streaks from appearing.


Excessive Cleaning Solution

If you’re using too much window cleaner or another type of cleaning solution, it can lead to streaks instead of preventing them.

This is because the solutions can leave a film on the glass that’ll attract dust and dirt and when you try to wipe it away, those particles will create streaks.

To avoid this, use only a small amount of cleaning solution on your windows. You can also try using distilled water instead as it won’t leave behind any minerals that cause streaking.


Wrong Equipment

Using the wrong equipment to clean your windows can also cause streaks. This is most common when using a paper towel or another material that’s not lint-free. The fibers get caught on the glass and leave behind streaks.

To avoid this, use a lint-free cloth or sponge when cleaning your windows. This will help prevent any streaks from being left behind.

Hard Water

If you have hard water, it can also lead to window streaks. This is because the minerals in hard water can build up on the glass and cause streaking when you try to wipe it away.

To avoid this, use a vinegar solution to help break down the minerals and prevent them from building up on your windows.


Finally, it’s worth noting that inexperience can also lead to window streaks. If you’re not used to cleaning windows, it can be easy to miss a spot or apply too much pressure – both of which can cause streaks.

To avoid this, take your time when cleaning your windows and check for any missed spots before you move on.

Contact Us

Window streaks can be frustrating, but by taking the time to understand what’s causing them, you can take steps toward preventing them in the future. Keep an eye out for the main causes of window streaks, and take care when cleaning your windows to avoid any issues.

If you live in a high-rise condo and would like expert support for window cleaning and maintenance, Blackout Projects is here to help. We’ve been assisting clients across Toronto and the GTA for years with all their window cleaning and restoration needs. Contact us today to learn more about our services!